1. Technical Field
The present disclosure relates generally to the halogenation and/or sulfonation of paraffins and, more particularly, to apparatus and methods for producing halogenated and/or sulfonated paraffins utilizing high shear. More specifically, this disclosure pertains to the reduction of mass transfer limitations for halogenating, sulfonating, or sulfo-halogenating a feed comprising paraffins.
2. Background of the Invention
Chlorinated paraffins (CPs), which were introduced in the 1930s, are a complex mixture of polychlorinated n-alkanes. The chlorination degree of CPs generally varies between about 30 and 70%. CPs are subdivided according to their carbon chain length into short chain CPs (SCCPs, C10-13), medium chain CPs (MCCPs, C14-17) and long chain CPs (LCCPs, C>17). Over 200 CP formulations are currently in use for a wide range of industrial applications, including application as flame retardants and plasticizers and as additives in metal working fluids, in sealants, paints and coatings.
The largest application for chlorinated paraffins is as a plasticizer. In flexible PVC, chlorinated paraffins are generally utilized in conjunction with primary plasticizers, such as various phthalates. The use of chlorinated paraffins in PVC imparts a number of benefits such as the enhancement of flame retardant properties. Such properties are of particular value in the production of PVC flooring and cables.
Chlorinated paraffins are also used as plasticizers in paint, sealants and adhesives, where the main advantages thereof over available alternatives are the relative inertness of CPs and the enhancement of flame retardant properties provided thereby. Chlorinated paraffins of higher chlorine content grades are utilized as flame retardants in a wide range of rubbers and polymer systems and may be preferable to phosphate and/or bromine-based additives.
Another major outlet for chlorinated paraffins is in the formulation of metal working lubricants. Chlorinated paraffins have long been recognized as one of the most effective extreme pressure additives for lubricants that find application in a gamut of machining and engineering operations.
U.S. Pat. No. 4,100,212 describes conventional processes for chlorination of linear paraffins. As noted therein, it is desirable to achieve a rapid and efficient homogenization of the liquid and gaseous reactants and it is often difficult to achieve complete conversion of reagent chlorine even with utilization of relatively long contact times.
Accordingly, there is a need in the industry for improved systems and methods for producing halogenated, sulfonated, or sulfo-halogenated paraffins, whereby costs may be reduced via operation at lower temperature and/or pressure, product yield may be increased, reaction time may be decreased, and/or capital and/or operating costs may be reduced. Desirably, conversion of reagent (e.g. chlorine or other halogen gas) is substantially complete and/or time of contact of feed material to be treated with treatment aid (e.g. reagent) is decreased via the method relative to conventional systems and methods.